valve or flange in "operational" 20" 70 bar steam pipe
valve or flange in "operational" 20" 70 bar steam pipe
(OP)
Dear Engineers,
I have a question, which is kind of a long shot, but I still want to ask it;
We have a 200 meter long 20" pipe which is fed at our factory its side with 75bar steam.
At the other side it will be double blocked.
These is no way to block the pipe at our side of the pipe for the next 3 years, and a plant stop is not really an option.
I way wondering or any of you have ever heard of a way to make a block in the pipe at our side, while the pipe is in operation?
It will not really be hot tapping, but maybe there is something comparable?
As a "visualisation", the situation is displayed below
I = block
--- = pipe
<- = 75 bar "flow" direction
customer I------------------------------<-- our factory
Thanks
I have a question, which is kind of a long shot, but I still want to ask it;
We have a 200 meter long 20" pipe which is fed at our factory its side with 75bar steam.
At the other side it will be double blocked.
These is no way to block the pipe at our side of the pipe for the next 3 years, and a plant stop is not really an option.
I way wondering or any of you have ever heard of a way to make a block in the pipe at our side, while the pipe is in operation?
It will not really be hot tapping, but maybe there is something comparable?
As a "visualisation", the situation is displayed below
I = block
--- = pipe
<- = 75 bar "flow" direction
customer I------------------------------<-- our factory
Thanks





RE: valve or flange in "operational" 20" 70 bar steam pipe
You should also look it up on the web and read about it so you can talk to the Contractor.
Look here:
https://www.google.com/search?q=stopple&tbm=is...
prognosis: Lead or Lag
RE: valve or flange in "operational" 20" 70 bar steam pipe
As pennpiper said, use a line stop device such as a stopple. Depending on how reliable you need for the containment to be, consider installing the stopple, then cutting the pipe a few meters away and installing a flange with a blind. You could use an end cap but you mention three years which to me implies you may want to return this line to service sometime. In that case, pay a bit more for steel and use the flange, as it will make the return to service easier. When you do put it back into service, install a valve first - stopples are ok for one-time stops, but not reliable for multiple uses since the cut edge that the device seals on will not be a clean cut (i.e. it will have corroded a bit) the next time you try to seal against it.
jt
RE: valve or flange in "operational" 20" 70 bar steam pipe
The option for a Stopple sounds very usefull indeed. Thank you for the suggestion.
I have not found a case online jet where it is used in a 80 bar 480 C (653 K) running steam pipe, but a further contact with some of the suppliers of the system should give more information about that.
Maarten
RE: valve or flange in "operational" 20" 70 bar steam pipe
As with a stopple, it's really a temporary thing to allow you to fit a valve or removable blind, but doesn't require a permanent fitting on the pipe like a stopple.
Also there are newer plug type systems such as http://www.petersenproducts.com/hot_tap_systems.as...
which only require a smaller flange connection. You need to talk to some vendors to see if they do your pressure and temperature.
good luck
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way